The cold forging of a tubular member into an annular member such as a well hanger or a connector has been known in the past. The cold forging has also been used to form a tubular member into an annular connector in a remote location, such as in a subsea pipeline repair. This is shown in U.S. Pat. Nos. 3,432,916 and 4,330,144. U.S. Pat. No. 4,662,663 discloses the use of pressure compensating material between the two members being cold formed and such material prevents the buildup of pressure which would prevent the proper completion of the cold forming.
A tool previously used in this type of cold forging process is shown in U.S. Pat. No. 4,388,752. This tool includes an alloy shaft having a shoulder on one end and a ring surrounding the other end and a rubber tube expansion element surrounding the shaft with annular nylon rings engaging the ends of the rubber expansion element and alloy rings supporting the exterior of each of the nylon rings. The radial force is developed by the tool response to longitudinal forced exerted on the expansion element. The nylon rings are provided to prevent extrusion of the rubber expansion element.
Other tools have been suggested which include a resilient tubular member which is exposed to hydraulic pressure internally and secured at its ends and is allowed to exert outward radial forces to cold forge a tubular member into the interior of an annular member.